The long-term objective of this research is to contribute to the understanding of factors associated with contraceptive continuation among teenage family planning clients. A systematic explanatory framework has been developed in which continuation is hypothesized to be a function of two sets of variables: pre-existing attitudes and beliefs which the young woman brings with her to the family planning clinic and her response to the clinic experience itself. A psychosocial model incorporating the former set of variables is based on existing models of health behavior: the latter set of variables is derived from the sociological literature on clients and organizations. Employing data collection instruments developed on the basis of this framework, baseline and two waves of follow-up interviews have been completed with 2,100 young women, unmarried and under 20 when they were initially interviewed as first-time clients of 78 Maryland county health department family planning clinics. Clinic records for a twelve-month period subsequent to the clinic visit were abstracted, and interview and questionnaire data were obtained from nurse and physician clinic staff. The specific aim of this application is to obtain support for a series of analyses based on these data. These analyses will test specific hypotheses derived from the explanatory framework described above and will attempt to specify in some detail the individual and delivery system conditions most likely to facilitate continued contraceptive use by sexually active teenagers. Ineffective contraceptive use and unwanted pregnancy continue to be significant problems among U.S. teenagers. The planned data analyses will both add to knowledge of factors that contribute to these problems and also, because of its focus on delivery system characteristics, provide a basis for programmatic intervention to improve contraceptive use.